This invention relates to an air bag assembly for use in a vehicle and more particularly to an air bag assembly including an inflatable cushion deployable from a storage location adjacent the lower edge of the vehicle windshield so as to extend over the lower portion of the vehicle windshield and the scuttle area between the lower edge of the vehicle windshield and the outwardly extending hood.
It is well known in the prior art to provide an air bag assembly including an inflatable air bag for protecting passengers seated within the interior of the vehicle. Such inflatable air bags may be deployable from a number of different locations at the interior of the vehicle including the steering column, the dash panel, the side doors, and the interior roofline. Such inflatable air bags may have a number of different configurations and inflation characteristics depending upon the location of deployment and the desired function. By way of example, air bag cushions which are deployable from the steering column and dash panel are typically rapidly inflated and thereafter decompressed as the occupant to be protected comes into contact with the air bag cushion. Alternatively, it is known to utilize air bags of generally curtain-like configuration deployable from the interior roof line which may thereafter remain inflated for an extended period of time so as to provide cushioning restraint during an extended roll over event lasting several seconds.
Air bag assemblies as are known in the prior art typically include a gas generating inflator which is stored in fluid communication with the inflatable air bag cushion. Upon sensing predetermined vehicle conditions, such as a certain amount of vehicle deceleration, a sensor sends a signal to the inflator thereby triggering the discharge of inflation gas into the air bag cushion. As the inflation gas enters the air bag cushion, the air bag cushion is forced into a deployed position for protection of the occupants within the interior of the vehicle. While the deployment of previously known air bag cushions within the interior of the vehicle may provide substantial benefits to the occupants of the vehicle, such systems provide no benefit to persons at the exterior of the vehicle. By way of example, in the event of a collision between a standard automobile and a bicycle operator or pedestrian, it is known that interaction may take place between the exterior surfaces of the automobile and such bicycle operator or pedestrian which interactions are not subject to cushioning by air bag cushions deployed at the interior of the vehicle. Injury may result in the event that the head of the person impacts outer surfaces of the vehicle which are not readily deformable and thus do not provide intrinsic energy dissipation.
The present invention offers advantages and alternatives over the prior art by providing an air bag assembly which is deployable over the lower portion of the vehicle windshield and the so-called scuttle area of the vehicle body adjacent the lower portion of the vehicle windshield so as to provide a cushion for persons outside the vehicle who may come into contact with such vehicle portions during a collision event and to thereby reduce the likelihood of injury to the head and other portions of the person""s body.
According to a potentially preferred feature of the present invention, the air bag cushion is deployable from a location which is substantially hidden from view by the hood of the vehicle prior to deployment.
According to another potentially preferred feature, the air bag cushion according to the present invention is characterized by a height dimension such that the air bag cushion extends only partially up the windshield of the vehicle during deployment thereby permitting the operator of the vehicle to maintain visibility with the exterior environment subsequent to the deployment of the air bag cushion.
According to yet a further potentially preferred feature of the present invention, the air bag cushion is characterized by a flared width dimension so as to provide coverage over at least a portion of the structural pillar elements extending between the windshield and the forward side windows of the vehicle.
According to one aspect of the present invention, these features are incorporated in a potentially preferred form of the invention by providing an air bag assembly for use in a vehicle at a location exterior to the passenger compartment. The air bag assembly preferably includes an inflator for discharging inflation gas and a gas receiving expansible air bag cushion disposed in fluid communication with the inflator such that upon release of inflation gas from the inflator, the air bag cushion is deployed across a region immediately below the windshield of the vehicle as well as over the lower portion of the windshield and adjacent portions of the frame surrounding the windshield. The extent of coverage over the windshield is preferably such that the vehicle operator retains a degree of visibility over the deployed air bag cushion after deployment has taken place. The materials forming the air bag cushion are preferably of an extremely low gas permeability and preferably comprise a textile material including an internal or external permeability blocking layer of suitable character. The total inflated volume of the air bag cushion is preferably relatively low so as to permit the use of a single low volume inflator if desired. Thus, this invention provides a system of unobtrusive character for cushioning the impact of a person external to the occupant compartment of an automotive vehicle which advantageously covers portions of the vehicle exterior against which such a person may be likely to come into contact during an impact event with the vehicle. In addition, the air bag cushion does not substantially obstruct the vision of the vehicle operator upon deployment and thereby permits the operator to engage in the continued operation of the vehicle in an appropriate manner.